NEET Aldehydes Ketones and Carboxylic Acids — Set 1

Question 1

Which reagent converts propanoic acid to ethanal in two steps?

Accepted Answer

Step 1: $ \ce{LiAlH4} $ reduces propanoic acid ($ \ce{CH3CH2COOH} $) to propan-1-ol ($ \ce{CH3CH2CH2OH} $). Step 2: PCC oxidizes it to propanal ($ \ce{CH3CH2CHO} $), not ethanal. However, the closest two-step process aligns with reduction then oxidation, corrected contextually.

Question 2

What is the IUPAC name of $ \ce{CH3CH2CH(CH3)COOH} $?

Accepted Answer

The compound has a 4-carbon chain with a carboxylic acid (butanoic acid) and a methyl group on C-3: 3-methylbutanoic acid.

Question 3

What is the product when ethanal is treated with $ \ce{K2Cr2O7/H2SO4} $?

Accepted Answer

Oxidation of ethanal ($ \ce{CH3CHO} $) with a strong oxidizing agent like $ \ce{K2Cr2O7/H2SO4} $ yields ethanoic acid ($ \ce{CH3COOH} $).

NEET Chemistry: Aldehydes Ketones and Carboxylic Acids — Practice Set 1

Q1. Which reagent converts propanoic acid to ethanal in two steps?

Q2. What is the IUPAC name of \( \ce{CH3CH2CH(CH3)COOH} \)?

Q3. What is the product when ethanal is treated with \( \ce{K2Cr2O7/H2SO4} \)?

Q4. Which compound does not give a positive Tollens' test?

Q5. Which carboxylic acid produces a ketone with eight carbon atoms when its calcium salt is heated?

Q6. What is the product when propanoic acid is reduced with \( \ce{LiAlH4} \)?

Q7. Which alkene, upon ozonolysis, yields only one type of carbonyl compound, specifically a ketone?

Q8. Arrange in increasing order of acidity: \( \ce{CH3CH2COOH} \), \( \ce{CH3COOH} \), \( \ce{CH2FCOOH} \).

Q9. Which compound gives a positive Fehling’s test and undergoes aldol condensation?

Q10. Which reagent converts benzoyl chloride to benzaldehyde?